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Forget about blasting dangerous orbiting objects out of the sky with laser beams. Dr Ben Greene would be happy to give them a gentle nudge.

The chief scientist and chief executive officer of the Mount Stromlo-based Electro Optic Systems, Dr Greene is in charge of a program that will allow hazardous space junk as small as a centimetre in diameter orbiting the Earth to be mapped.

Within two years, helped by an $8.4 million Federal Government grant, the company also hopes to test a laser system that can send a beam into space from Earth and push orbiting rubbish away from collision paths with satellites.

While there are many millions of pieces of rubbish and waste that are now zooming around the planet in low orbit, somewhere between 100,000 and 200,000 of these are bigger than a centimetre.

These objects, which range from globules of fuel to an astronaut's glove to massive fuel tanks from Russian spacecraft, pose potentially catastrophic threats to satellites.

According to NASA, there are tonnes of debris left on the moon, Venus and Mars, and up to hundreds of millions of pieces of "space trash" floating through our region of the solar system.

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Space trash in orbits lower than 600 kilometres usually falls back to Earth within a few years, but objects in orbit above 1000 kilometres may stay up for centuries.

"A one-centimetre object in space will hit you like a Mack truck doing 100 kilometres per hour," Dr Greene said.

Already the company has several undisclosed clients whose satellites are kept safe by the maps. Previous tracking of space debris was done by radar, and was slower and less accurate than the new laser system.

"Everything that goes up in space finishes up in the junk heap eventually. They're all man-made and they're mostly debris from accidents in space or carelessness.

Of greatest concern to satellite manufacturers is that the rubbish is everywhere in low orbit. "You look anywhere in the sky with a laser and you will see this stuff," Dr Greene said. "It's like catching butterflies - you need a butterfly net with fine enough mesh to catch them."

His company has tracked the glove lost by an astronaut. "It's really quite big and bright," he said. But the real test of the new technology will be the current program of shifting rubbish by laser. A real test could be done within two years.

"We have embarked on a program to be able to move things in space from the ground," Dr Greene said.

"It would be nice to be able to move the debris rather than the satellite."